Researchers from the University of Indonesia’s Faculty of Engineering, Metallurgy and Materials Engineering Department (DTMM FTUI) have found an innovative way to use coffee grounds as a component inside lithium-ion batteries that might help improve performance and reduce the need for environmentally damaging materials.
Lithium-ion batteries are ubiquitous in our modern-day lives, and in particular, form the platform on which modern-day electric vehicles are built. However, they come with several problems practical and environmental, which this discovery may help alleviate.
Perversely, the first problem is that lithium-ion batteries and cells do not contain environmentally friendly components. Lithium itself is a metal mined at a high cost to the environment by requiring vast quantities of water, often at the expense of local wildlife. Two other materials, cobalt and nickel, are mined under harsh conditions. They also come with an impact on the environment.
So an immediate Challenge for improving the sustainability of these batteries is to substitute some of those problematic materials for a more sustainable option.
This is where researchers in Indonesia think they might have made the first steps towards a solution by using waste coffee grounds.
Our team attempts to overcome the weaknesses of mixing Sn or Si and active carbon from coconut shell waste into composites. We also turn coffee waste grounds into graphene which will be mixed with LTO (Lithium Titanate Oxide, used to reduce short circuits while the battery is charging, increasing safety)Head of the Lithium-Ion battery development research team, Anne Zulfia Syahrial
The team’s first step is to carbonise the coffee grinds by heating them to 800 degrees, from which they create graphene. Graphene itself is an interesting material. It is only one atom thick yet hundreds of times stronger than steel of the same thickness. Some of the properties of graphene are that it is very good at conducting electricity and in making that flow of electrons predictable and consistent. This is also key to improving safety (remember the year the Samsung Galaxy Note phones were banned from aeroplanes because they were a fire hazard)
The graphene is used as the battery’s anodes – which is responsible for discharging power and allowing power to flow back in when recharging.
The researchers point out that current graphite-based lithium batteries are significantly larger and heavier and take longer to charge.
The team has challenged themselves to make a battery at less than half the weight of current models, to perhaps as low as 200kg from the current 500kg of existing batteries. This would have the effect of increasing the range a vehicle can travel since it would have an improved power to weight ratio.
The research shows that Indonesia has a huge potential to become a market leader in terms of EV batteries, with the abundance of materials that can be used to produce batteries that are available in Indonesia’s nature,The University of Indonesia Engineering Faculty Dean Hendri D.S. Budiono
The paper also refers to super-fast charging times of perhaps just 15 minutes versus the several hours it currently takes to charge an electric car fully. While this sounds amazing, the concept of what is known as supercapacitors have been a dream for years. In fact, they already exist, and I own a power drill that charges in 30 seconds and lasts 30 mins. However, the technology has never scaled to larger batteries.
There is much competition to solve this problem, however. For example, an article in the Guardian newspaper this January described an Israeli company that also claimed to recharge car batteries in 5 minutes.
We often see stories about the uses of waste coffee grounds. However, suppose the researchers are successful in their design. It could be the most innovative application of coffee waste yet, contributing to designing environmentally friendly batteries that we will all depend on in the future.